Amy R. Kahn

Spectrum of Cancer Risk Among US Solid Organ Transplant Recipients

CONTEXT Solid organ transplant recipients have elevated cancer risk due to immunosuppression and oncogenic viral infections. Because most prior research has concerned kidney recipients, large studies that include recipients of differing organs can inform cancer etiology. OBJECTIVE To describe the overall pattern of cancer following solid organ transplantation. DESIGN, SETTING, AND PARTICIPANTS Cohort study using linked data on solid organ transplant recipients from the US Scientific Registry of Transplant Recipients (1987-2008) and 13 state and regional cancer registries. MAIN OUTCOME MEASURES Standardized incidence ratios (SIRs) and excess absolute risks (EARs) assessing relative and absolute cancer risk in transplant recipients compared with the general population. RESULTS The registry linkages yielded data on 175,732 solid organ transplants (58.4% for kidney, 21.6% for liver, 10.0% for heart, and 4.0% for lung). The overall cancer risk was elevated with 10,656 cases and an incidence of 1375 per 100,000 person-years (SIR, 2.10 [95% CI, 2.06-2.14]; EAR, 719.3 [95% CI, 693.3-745.6] per 100,000 person-years). Risk was increased for 32 different malignancies, some related to known infections (eg, anal cancer, Kaposi sarcoma) and others unrelated (eg, melanoma, thyroid and lip cancers). The most common malignancies with elevated risk were non-Hodgkin lymphoma (n = 1504; incidence: 194.0 per 100,000 person-years; SIR, 7.54 [95% CI, 7.17-7.93]; EAR, 168.3 [95% CI, 158.6-178.4] per 100,000 person-years) and cancers of the lung (n = 1344; incidence: 173.4 per 100,000 person-years; SIR, 1.97 [95% CI, 1.86-2.08]; EAR, 85.3 [95% CI, 76.2-94.8] per 100,000 person-years), liver (n = 930; incidence: 120.0 per 100,000 person-years; SIR, 11.56 [95% CI, 10.83-12.33]; EAR, 109.6 [95% CI, 102.0-117.6] per 100,000 person-years), and kidney (n = 752; incidence: 97.0 per 100,000 person-years; SIR, 4.65 [95% CI, 4.32-4.99]; EAR, 76.1 [95% CI, 69.3-83.3] per 100,000 person-years). Lung cancer risk was most elevated in lung recipients (SIR, 6.13 [95% CI, 5.18-7.21]) but also increased among other recipients (kidney: SIR, 1.46 [95% CI, 1.34-1.59]; liver: SIR, 1.95 [95% CI, 1.74-2.19]; and heart: SIR, 2.67 [95% CI, 2.40-2.95]). Liver cancer risk was elevated only among liver recipients (SIR, 43.83 [95% CI, 40.90-46.91]), who manifested exceptional risk in the first 6 months (SIR, 508.97 [95% CI, 474.16-545.66]) and a 2-fold excess risk for 10 to 15 years thereafter (SIR, 2.22 [95% CI, 1.57-3.04]). Among kidney recipients, kidney cancer risk was elevated (SIR, 6.66 [95% CI, 6.12-7.23]) and bimodal in onset time. Kidney cancer risk also was increased in liver recipients (SIR, 1.80 [95% CI, 1.40-2.29]) and heart recipients (SIR, 2.90 [95% CI, 2.32-3.59]). CONCLUSION Compared with the general population, recipients of a kidney, liver, heart, or lung transplant have an increased risk for diverse infection-related and unrelated cancers.

Survival after cancer diagnosis in persons with AIDS

The survival of persons with AIDS (PWA) has recently improved because of better antiretroviral therapies. Similarly, the prognosis of cancer has also improved. To determine if survival in PWA with cancer has also improved, we compared cancer survival in adults with and without AIDS using data from New York City from 1980 through 2000. Analyses were made for AIDS-related cancers (Kaposi sarcoma, non-Hodgkin lymphoma [NHL], and cervical cancer) and for 8 non-AIDS-related cancers (lung, larynx, colorectum, anus, Hodgkin lymphoma, breast, prostate, and testis). Death hazard ratios compared survival in PWA with cancer with that in cancer patients without AIDS, adjusted for age, sex, race, and calendar-time of cancer occurrence. The 24-month survival rate of PWA with cancer (9015 AIDS cancers and 929 non-AIDS-related cancers of 8 types) improved significantly for most cancer types. By 1996 through 2000, the 24-month survival rate in PWA was 58% for Kaposi sarcoma, 41% for peripheral NHL, 29% for central nervous system NHL, and 64% for cervical cancer. For non-AIDS-related cancers, survival of PWA was lowest for lung cancer (10%) but was >50% for most other cancer types. In 1996 through 2000, significant differences in survival between cancer patients with and without AIDS still remained for Hodgkin lymphoma and lung, larynx, and prostate cancers. We conclude that recent improvements in AIDS and cancer care have greatly narrowed the gap in survival between cancer patients with and without AIDS. Clinicians should be encouraged by the improving prognosis and be diligent about detecting and treating cancer in PWA.

Factors associated with initial treatment and survival for clinically localized prostate cancer: results from the CDC-NPCR Patterns of Care Study (PoC1)

BackgroundDespite the large number of men diagnosed with localized prostate cancer, there is as yet no consensus concerning appropriate treatment. The purpose of this study was to describe the initial treatment patterns for localized prostate cancer in a population-based sample and to determine the clinical and patient characteristics associated with initial treatment and overall survival.MethodsThe analysis included 3,300 patients from seven states, diagnosed with clinically localized prostate cancer in 1997. We examined the association of sociodemographic and clinical characteristics with four treatment options: radical prostatectomy, radiation therapy, hormone therapy, and watchful waiting. Diagnostic and treatment information was abstracted from medical records. Socioeconomic measures were derived from the 2000 Census based on the patients residence at time of diagnosis. Vital status through December 31, 2002, was obtained from medical records and linkages to state vital statistics files and the National Death Index. Multiple logistic regression analysis and Cox proportional hazards models identified factors associated with initial treatment and overall survival, respectively.ResultsPatients with clinically localized prostate cancer received the following treatments: radical prostatectomy (39.7%), radiation therapy (31.4%), hormone therapy (10.3%), or watchful waiting (18.6%). After multivariable adjustment, the following variables were associated with conservative treatment (hormone therapy or watchful waiting): older age, black race, being unmarried, having public insurance, having non-screen detected cancer, having normal digital rectal exam results, PSA values above 20, low Gleason score (2-4), comorbidity, and state of residence. Among patients receiving definitive treatment (radical prostatectomy or radiation therapy), older age, being unmarried, PSA values above 10, unknown Gleason score, state of residence, as well as black race in patients under 60 years of age, were associated with receipt of radiation therapy. Overall survival was related to younger age, being married, Gleason score under 8, radical prostatectomy, and state of residence. Comorbidity was only associated with risk of death within the first three years of diagnosis.ConclusionsIn the absence of clear-cut evidence favoring one treatment modality over another, it is important to understand the factors that inform treatment selection. Since state of residence was a significant predictor of both treatment as well as overall survival, true regional differences probably exist in how physicians and patients select treatment options. Factors affecting treatment choice and treatment effectiveness need to be further explored in future population-based studies.

Association Between World Trade Center Exposure and Excess Cancer Risk

CONTEXT The terrorist attacks of September 11, 2001, resulted in the release of known and suspected carcinogens into the environment. There is public concern that exposures may have resulted in increased cancers. OBJECTIVE To evaluate cancer incidence among persons enrolled in the World Trade Center Health Registry. DESIGN, SETTING, AND PARTICIPANTS Observational study of 55,778 New York State residents enrolled in the World Trade Center Health Registry in 2003-2004, including rescue/recovery workers (n = 21,850) and those not involved in rescue/recovery (n = 33,928), who were followed up from enrollment through December 31, 2008. Within-cohort comparisons using Cox proportional hazards models assessed the relationship between intensity of World Trade Center exposure and selected cancers. MAIN OUTCOME MEASURES Cases were identified through linkage with 11 state cancer registries. Standardized incidence ratios (SIRs) adjusted for age, race/ethnicity, and sex were computed with 2003-2008 New York State rates as the reference, focusing on cancers diagnosed in 2007-2008 as being most likely to be related to exposure during September 11 and its aftermath. The total and site-specific incidence rate differences (RDs) per 100,000 person-years between the study population and the New York State population in 2007-2008 also were calculated. RESULTS There were 1187 incident cancers diagnosed, with an accumulated 253,269 person-years (439 cancers among rescue/recovery workers and 748 among those not involved in rescue/recovery). The SIR for all cancer sites combined in 2007-2008 was not significantly elevated (SIR, 1.14 [95% CI, 0.99 to 1.30]; RD, 67 [95% CI, -6 to 126] per 100,000 person-years among rescue/recovery workers vs SIR, 0.92 [95% CI, 0.83 to 1.03]; RD, -45 [95% CI, -106 to 15] per 100,000 person-years among those not involved in rescue/recovery). Among rescue/recovery workers, the SIRs had significantly increased by 2007-2008 for 3 cancer sites and were 1.43 (95% CI, 1.11 to 1.82) for prostate cancer (n = 67; RD, 61 [95% CI, 20 to 91] per 100,000 person-years), 2.02 (95% CI, 1.07 to 3.45) for thyroid cancer (n = 13; RD, 16 [95% CI, 2 to 23] per 100,000 person-years), and 2.85 (95% CI, 1.15 to 5.88) for multiple myeloma (n = 7; RD, 11 [95% CI, 2 to 14] per 100,000 person-years). No increased incidence was observed in 2007-2008 among those not involved in rescue/recovery. Using within-cohort comparisons, the intensity of World Trade Center exposure was not significantly associated with cancer of the lung, prostate, thyroid, non-Hodgkin lymphoma, or hematological cancer in either group. CONCLUSIONS Among persons enrolled in the World Trade Center Health Registry, there was an excess risk for prostate cancer, thyroid cancer, and myeloma in 2007-2008 compared with that for New York State residents; however, these findings were based on a small number of events and multiple comparisons. No significant associations were observed with intensity of World Trade Center exposures. Longer follow-up for typically long-latency cancers and attention to specific cancer sites are needed.

Cancer Incidence in World Trade Center Rescue and Recovery Workers, 2001–2008

Background: World Trade Center (WTC) rescue and recovery workers were exposed to a complex mix of pollutants and carcinogens. Objective: The purpose of this investigation was to evaluate cancer incidence in responders during the first 7 years after 11 September 2001. Methods: Cancers among 20,984 consented participants in the WTC Health Program were identified through linkage to state tumor registries in New York, New Jersey, Connecticut, and Pennsylvania. Standardized incidence ratios (SIRs) were calculated to compare cancers diagnosed in responders to predicted numbers for the general population. Multivariate regression models were used to estimate associations with degree of exposure. Results: A total of 575 cancers were diagnosed in 552 individuals. Increases above registry-based expectations were noted for all cancer sites combined (SIR = 1.15; 95% CI: 1.06, 1.25), thyroid cancer (SIR = 2.39; 95% CI: 1.70, 3.27), prostate cancer (SIR = 1.21; 95% CI: 1.01, 1.44), combined hematopoietic and lymphoid cancers (SIR = 1.36; 95% CI: 1.07, 1.71), and soft tissue cancers (SIR = 2.26; 95% CI: 1.13, 4.05). When restricted to 302 cancers diagnosed ≥ 6 months after enrollment, the SIR for all cancers decreased to 1.06 (95% CI: 0.94, 1.18), but thyroid and prostate cancer diagnoses remained greater than expected. All cancers combined were increased in very highly exposed responders and among those exposed to significant amounts of dust, compared with responders who reported lower levels of exposure. Conclusion: Estimates should be interpreted with caution given the short follow-up and long latency period for most cancers, the intensive medical surveillance of this cohort, and the small numbers of cancers at specific sites. However, our findings highlight the need for continued follow-up and surveillance of WTC responders.

Mortality among semiconductor and storage device-manufacturing workers.

Problem: We evaluated mortality during 1965 to 1999 among 126,836 workers at two semiconductor facilities and one storage device facility. Method: We compared employees’ cause-specific mortality rates with general population rates and examined mortality patterns by facility, duration of employment, time since first employment, and work activity. Results: Employees had lower-than-expected mortality overall (6579 observed deaths, standardized mortality ratio [SMR] = 65; 95% confidence interval [CI] = 64–67), for all cancers combined (2159 observed, SMR = 78, 95% CI = 75–81) and for other major diseases. Central nervous system cancer was associated with process equipment maintenance at one of the semiconductor facilities (10 observed, SMR = 247, 95% CI = 118–454). Prostate cancer was associated with facilities/laboratories at the storage device facility (18 observed, SMR = 198, (5% CI = 117–313). Conclusions: Further evaluation of workplace exposures or independent investigations of similar occupational groups may clarify the interpretation of associations observed in this study

Melanoma Risk and Survival among Organ Transplant Recipients

Solid organ transplant recipients, who are medically immunosuppressed to prevent graft rejection, have increased melanoma risk, but risk factors and outcomes are incompletely documented. We evaluated melanoma incidence among 139,991 non-Hispanic white transplants using linked U.S. transplant-cancer registry data (1987–2010). We used standardized incidence ratios (SIRs) to compare incidence to the general population, and incidence rate ratios (IRRs) from multivariable Poisson models to assess risk factors. Separately, we compared post-melanoma survival among transplant recipients (N=182) and non-recipients (N=131,358) using multivariable Cox models. Among transplant recipients, risk of invasive melanoma (N=519) was elevated (SIR=2.20, 95%CI 2.01-2.39), especially for regional stage tumors (SIR=4.11, 95%CI 3.27–5.09). Risk of localized tumors was stable over time after transplantation, but higher with azathioprine maintenance therapy (IRR=1.35, 95%CI 1.03–1.77). Risk of regional/distant stage tumors peaked within 4 years following transplantation and increased with polyclonal antibody induction therapy (IRR=1.65, 95%CI 1.02–2.67). Melanoma-specific mortality was higher among transplant recipients than non-recipients (HR 2.98, 95%CI 2.26–3.93). Melanoma exhibits increased incidence and aggressive behavior under transplant-related immunosuppression. Some localized melanomas may result from azathioprine, which acts synergistically with ultraviolet radiation, while T-cell depleting induction therapies may promote late stage tumors. Our findings support sun safety practices and skin screening for transplant recipients.

Surgical staging of early stage epithelial ovarian cancer: Results from the CDC-NPCR ovarian patterns of care study

OBJECTIVES The objectives of this study were to determine the adequacy of surgical staging performed on surgically treated epithelial ovarian cancer (EOC) patients with apparent early stage disease and to determine if receipt of surgical staging had an influence on survival. METHODS Detailed surgical staging information was collected from medical records for 721 patients diagnosed between 1998 and 2000 with EOC. Patients resided in California or New York and were identified through population-based cancer registries. RESULTS Nearly 90% of patients had removal of the omentum and evaluation of bowel serosa and mesentery but only 72% had assessment of retroperitoneal lymph nodes and the majority of patients did not receive biopsies of other peritoneal locations. Only lymph node assessment (as well as node assessment combined with washings and omentectomy) had a statistically significant association with improved survival. The 5-year survival for women with node sampling was 84.2% versus 69.6% for those without this surgical procedure, and patients who did not have lymph node assessment had nearly twice the risk of death as those who did. When patients were stratified by receipt of chemotherapy, lack of node sampling had an effect only on patients who also had no chemotherapy (adjusted HR=2.2, CI=1.0-4.5). CONCLUSIONS The results of this population-based study confirm the prognostic importance of surgical staging for women with EOC, and the important role of gynecologic oncologists in treating these patients. Adjuvant chemotherapy does not appear to further improve survival for those women who receive adequate surgical staging.

Cancer incidence among semiconductor and electronic storage device workers

Aims: To evaluate cancer incidence among workers at two facilities in the USA that made semiconductors and electronic storage devices. Methods: 89 054 men and women employed by International Business Machines (IBM) were included in the study. We compared employees’ incidence rates with general population rates and examined incidence patterns by facility, duration of employment, time since first employment, manufacturing era, potential for exposure to workplace environments other than offices and work activity. Results: For employees at the semiconductor manufacturing facility, the standardised incidence ratio (SIR) for all cancers combined was 81 (1541 observed cases, 95% confidence interval (CI) 77 to 85) and for those at the storage device manufacturing facility the SIR was 87 (1319 observed cases, 95% CI 82 to 92). The subgroups of employees with ≥15 years since hiring and ≥5 years worked had 6–16% fewer total incidents than expected. SIRs were increased for several cancers in certain employee subgroups, but analyses of incidence patterns by potential exposure and by years spent and time since starting in specific work activities did not clearly indicate that the excesses were due to occupational exposure. Conclusions: This study did not provide strong or consistent evidence of causal associations with employment factors. Data on employees with long potential induction time and many years worked were limited. Further follow-up will allow a more informative analysis of cancer incidence that might be plausibly related to workplace exposures in the cohort.

Disentangling the effects of race/ethnicity and socioeconomic status of neighborhood in cancer stage distribution in New York City

PurposeStage at diagnosis is an important prognostic factor for the majority of cancers; it may be an indicator for quality of access to health care and is usually correlated with socioeconomic status (SES) and ethnicity/race. We aimed to investigate the association between stage of cancer at diagnosis with neighborhood of residence (as proxy for SES) and ethnicity/race, while controlling for each other, in selected areas of New York City (NYC).MethodsThe cancer summary data (1999–2008) were provided by the New York State Cancer Registry. Multinomial logistic regression models were applied to calculate risk estimates for being diagnosed with late- or unknown-stage (versus early-stage) cancers in two low-SES and two high-SES neighborhoods of NYC and among several ethnic/racial groups for all cancers combined and cancers of the female breast, lung, colorectum, and prostate, with additional adjustments for sex (for all cancers combined), age, and year of diagnosis.ResultsA total of 34,981 cancer cases were included in this study. There were significant and independent ethnic/racial and neighborhood disparities in stage of cancer at diagnosis of most of the cancers studied. The effect of ethnicity/race on the disparity appeared stronger than the effect of neighborhood. There was an overall decreasing trend in the proportion of late-stage cancers, particularly for colorectal cancer, and to a greater extent in the proportion of cancers without staging information.ConclusionsIn this population, ethnicity/race seems to be a stronger predictor for late stage at diagnosis than SES, stressing the need for ethnicity/race-oriented programs for cancer screening and improved access to care.